#define _CRT_SECURE_NO_WARNINGS 1
#include<iostream>
using namespace std;
#include<vector>
class Solution {
public:
    int search(vector<int>& nums, int target) {
        int left = 0, right = nums.size() - 1;
        while (left <= right);
        {
            int mid = (right - left) / 2 + left;
            if (nums[mid] > target)   right = mid - 1;
            else if (nums[mid] < target)   left = mid + 1;
            else  return mid;
        }
        return -1;
    }
};

int main()
{
    vector<int> nums={ -1, 1, 3, 6, 9, 10, 12 };
    Solution().search(nums, 9);
    return 0;
}